The МХО37H/R series utilizes the internal heated resonator technology (IHR) providing very small oscillator volume, less than 0.18W power consumption and fast warming up. Usage of the internal multiplication of frequency (by 3 or 5) enables to the oscillators extension of the operational frequencies up to 300 MHz and improvement of the temperature stability and aging rate in 30-150 MHz range. Being enclosed in hermetically sealed steel packaging the МХО37/R oscillators are intended for employment in harsh environmental conditions (100% humidity, high or low pressure, etc.) and are excellent solution for various portable or (and) battered systems.